Reinforced-concrete dam.



How'AnnpL. commu, or aosrom MASSACHUSETTS, 'A ssreN'oa To A'ntamasnivHYDRAULIC CoNsT'aUCTroN CQMPANY, or BosToN, MASSACHUSETTS, Acda?PonATgtoN or Naw massif.

-inErNroRCnD-CQNCRETE DAM.

Specification of Letters Patent.

Application filed February 25;l 1908. 4Serial No.v 1=17,651.

Be i known Athat I, HOWARD L. COBURN, of Boston, in the county ofSuffolkand State of Massachusetts, .have invented certain new and usefulImprovements in Reinforced- Concrete Dams, vfwhich the following is aspecification,` y

This ,inyen'tionrelates to dams constructed of reinforced concrete, andhas for its particular. 'object to r improve the construction of they'decks orV water-bearing faces of such dams. Usually the dec-k of a damis an inclinedjwall, and'when made of concrete /is continuous from endto end; r'In the present invention in order lto minimize the liabilityof the deck 'to 'Warp and check, AI form the same from a number ofseparate slabs which are connected with supporting and stifeningbuttresses in such a way as to be firmly held in place, and areso joinedto the buttresses'fas to prevent leakage' past -their'adjacent portions.

Of the accompanying drawings,-Figure l represents a perspective View of'a portion of the dam embodyingthe Ininciples. of the present invention.Fig. 2 represents a fragmentary4 cross section of the same, showing thedetails of construction by which the vdeck slabs are supported andconnectedwith Athe buttresses so as to prevent leakage.

The same reference characters indicate the-same parts in both figures.

In constructing the dam a number of thin buttresse's A are built side byside and at the necessary distance apart, located in such a way as tooppose their greatest dimensions to the' pressure of the wat-er backedup by the dam. TheXtupst-ream edges or ends of the buttresses are formedwith an inclina-v tionor slant corresponding to that to be given to theface of the dam, while a short distance back from the edges are formedbrackets or haunches B. The upstream faces of these brackets projectperpendicularly from the central planes ofthe buttresses,

while the opposite portions taper gradually inward and merge with thebuttresses in such a .way as to furnish the maximum' strength. Inaddition, they are suitably reinforced by steel rods, as indicated inFig.

2. The bearing faces B of the brackets eX- allow for the variation inthickness vof the jdeck necessary to support the increased head of`water toward the foot of the dam.

Patented. July 30,1912.

in a downward direction, however, so as to Between the buttresses andresting against the brackets are placed the slabsC which `form' thedeck. Theseslabs are wholly separate from each other, being divided bythe projecting end portions E'bf the buttresses, with which their outersurfaces are The-brackets support the'ends of 'the slabs so as tosustain the hydrostatic head, while the tensilelstresses in theunsupported por-" tions are taken by the metal reinforcing' rods shownin Fig. 2.-

Hush.

In order toV prevent leakage; of water be-- tween the ends of the sljabs"and'jthe b1 1t''A tresses, the projecting portions E of thelat' ter areformed when being castwith grooves D and D', into whichcorrespondinglyshaped tongues jonthe ends 'of theslabs proj ject. As the4slabs 'are cast in place, the con# creto.being thus plastic, is causedtof into and fill thegrooves D D',

Each slab extends continuously from f the foot ofthe crest'- of the dam,but as before stated; is wholly independentand cilietinch` from eachofthe other slabs. Thusany distortion-which-may take place in the dam willbe localized and will cause no other eff fect than to slightly separatethe end of one or more of the slabs from theadjacent buttress, therebeing no liability, however, of

any part of the' deck to crack. In case of which will be unable to passthrough the' openings and thus eifectually seal them.

I claim 1. A reinforced-concrete dam consisting of transverse buttressesof reinforced concrete set edgewise to the ilow of the stream and havinglateralbracket-s near their upstream edges, but at a distance'therefromequal about to the thickness of the deck, and

a deck or upstream facecomposed of independent reinforced concrete'slabs between.

the bttresses extending slant'ingly'from the bottom to' v the'topgthereof and restin against said brackets, said deck being iiusv'witli; the upstreamA edges of said buttresses.

l2.1A dam comprising buttresses set edge- .lwiselto the'ow ofthevstream, each having brackets at its sides near the upstream edge,

'said brackets having bearing faces dlverging 'from Such edge from" topt-o bottom of the "buttress,4 andv de cleyslabs of'` reinforced con- 10crete 'castfin plac'between the but-tresses with their upper facesvsubstantially 4flush 'wit-h'the edge faces of the buttresses and v'their.under faces. in th'e plane of the brac-ktance between such surfaces and'the upstream edges of the buttresses.

5. A reinforced-concrete dam, consisting of buttresses and separateslabs of reinforced concrete forming the deck of /theidam cast in placeso as to extend between the buttrcsses,

the latter having lateral grooves interlocked with tongues in the edgesthe slabs t-o preventN leakage, and having also brackets in back of theedges of the slabs.

6. A reinforced-concrete dam, consisting of buttresses and separateslabs forming the deck of the dam extending across befete', whereby suchdeck slabs are given a 15 raduaily increasing thickness frein top togott-om... .-gy'..v l

'y f3." A reinforcedQconcrete dam comprising butt'resses'set vedgewiseto the flow of the stream, and 'deck :slabs of reinforced concrete 29cast'in place between'adjacent buttresses, the

buttresses having lateral -supporting bracketslying back of. the endsofthe slabs,and f theislabs and buttresses having inter-engag- ,.'ing,'leakage-preventing tongues and grooves 2 5 vformed in theedges.4 of ,theslabs and the' sides ofthe butti-'esses between said brackets l and-the'upstream faces of the but-tresses.

41A dam"consi'sting of a deck, and butf tresses transverse .to the deck,said buttresses 30 having ylateral brackets near their upstream edges,.formed with lsupporting surfaces diverging downwardly from such edges,and the vdeck 'consistingof independent rein-- y:forcedconcrete slabscast in piacer between 35 adjacent buttre'sses with their ends-restingagainst the supporting surfaces of the brack- V ets andYthicknessgoverned by the disby 'a vcontinuous deck or wall is vprovidedwhich lis suitably supported Iagainst the'hydrostatic pressure andunited with :leakagen preventing oints.

- In ltestimony whereof I yhave affixed signature, in presence of twowitnesses.

, HOWARD L. COBURIL Witnesses: v v

S, E. RociiwELL', N.- F. AmnsEN. i

